import Vue from 'vue'
import VueRouter from 'vue-router'
import Home from '../components/Home.vue'
import Login from '../components/Login.vue'
import Users from '../components/user/Users.vue'
import Welcome from '../components/Welcome.vue'

Vue.use(VueRouter)

const routes = [
  {
    path: '/',
    redirect: '/login'
  },
  {
    path: '/login',
    component: Login
  },
  {
    path: '/home',
    component: Home,
    redirect: '/welcome',
    children: [
      {
        path: '/welcome',
        component: Welcome
      },
      {
        path: '/users',
        component: Users
      }
    ]
  }
]

const router = new VueRouter({
  routes
})

// 挂载路由导航守卫
router.beforeEach((to, from, next) => {
  // to 将要访问的路径
  // from 代表从哪个路径跳转而来
  // next 是一个函数， 表示放行   ①next()放行   ②next('/login')强制跳转
  if (to.path === '/login') return next() // 访问登录页，直接放行
  // 获取token
  const tokenStr = window.sessionStorage.getItem('token')
  if (!tokenStr) return next('/login') // 没有token 强制跳转
  next() // 否则(有token)直接放行
})

export default router
